Search Results

Search found 20904 results on 837 pages for 'disk performance'.

Page 89/837 | < Previous Page | 85 86 87 88 89 90 91 92 93 94 95 96  | Next Page >

  • DISK BOOT FAILURE after upgrading power supply

    - by Phenom
    After upgrading my power supply, I get the following error message when trying to boot into Windows 7. DISK BOOT FAILURE, INSERT SYSTEM DISK AND PRESS ENTER My Windows 7 installation is on a SATA hard drive. I'm able to fix this problem if I hook up my IDE hard drive, then it boots the SATA hard drive fine. I don't like this solution though because then that means my IDE hard drive is drawing power even though it isn't being used. Why would a newer power supply need the IDE hard drive hooked up just to boot into the SATA hard drive? There are no boot files on the IDE hard drive; it is completely empty. My old power supply did not need it hooked up in order to boot the SATA hard drive.

    Read the article

  • Updating windows xp hard drive controller from ubuntu live disk

    - by Joel
    The problem: When booting, I get a blue screen shortly after the Windows XP logo splash screen. The error code is 7b, and the second hex number is 0xC0000034. Based on this link (item 7) it appears the driver should be updated. Oddly, I made no changes to the drivers recently. I suspect it was something in a windows update or the newest upgrade of my antivirus (eset). But I digress. The BSOD makes me unable to boot into Windows at all, so I can't update the driver from there. I've run various bios-level diagnostics (including full surface scan) and the hd looks good. I'm also able to boot to an old ubuntu disk and read files from the hd. The question: Based on the above, it appears that I need to update the Windows hard drive controller from the ubuntu live disk. How do I do that?

    Read the article

  • Can't Read/Write the Hard disk used in NAS

    - by mgpyone
    I've lately purchased a Synology DS212j and I intended to use my two 3.5" HDs into it. One of them was in used as an external HD. Thus when I install these two unit in NAS, it asked me to formatted in order to used with its format (I think it's ext3?) . I installed the Disks and omit the formatting option. I just got another 3.5" Hard Disk now. I've installed it in the NAS. everything's fine. However, when I take out the (used) HD from the NAS and install back in the standalone casing, I found out that it can't be read from both OSX an Windows 7. I've tried with ext2sd and I only found 2GB portion of the whole 1.5 TB Hard Disk. Here's another reference from EASEUS Partition Master

    Read the article

  • turn off disable the performance cache

    - by jessie
    OK I run a streaming website and my CMS is giving me an error when uploading videos "Failed To Find Flength File" ok so I did some research. The answer I got from the coder was below. I did do all that, but the only thing I could not do is turn off what he refers to as performance cache, talked about in the last sentence... I am on a Cent OS Assuming the script is set up properly, you are probably dealing with some kind of write-caching. Some servers perform write-caching which prevents writing out the flength file or the entire CGITemp file during the upload. The flength file or the CGITemp file do not actually hit the disk until the upload is complete, making it worthless for reporting on progress during the upload. This may be fixed using a .htaccess file assuming your host supports them. Here is a link to an excellent tutorial on using .htaccess files. I strongly recommend giving it a quick read before attempting to install your own .htaccess file. 1. A mod_security module for Apache. To fix it just create a file called .htaccess (that's a period followed by "htaccess") and put the following lines in that file. Upload the file into the directory where the Uber-Uploader CGI ".pl" scripts resides, or in some directory above it (like your server's DOCUMENT_ROOT, i.e. the top-level of your webspace). htaccess files must be uploaded as ASCII mode, not BINARY. You may need to CHMOD the htaccess file to 644 or (RW-R--R--). # Turn off mod_security filtering. SecFilterEngine Off # The below probably isn't needed, # but better safe than sorry. SecFilterScanPOST Off If the above method does not work, try putting the following lines into the file SetEnvIfNoCase Content-Type \ "^multipart/form-data;" "MODSEC_NOPOSTBUFFERING=Do not buffer file uploads" mod_gzip_on No 2. "Performance Cache" enabled on OS X SERVER. If you're running OS X Server and the progress bar isn't working, it could be because of "performance caching." Apparently if ANY of your hosted sites are using performance caching, then by default, all sites (domains) will attempt to. The fix then is to disable the performance cache on all hosted sites.

    Read the article

  • Volume expanded in Volume Group, old disk reduced but still in use in system

    - by Yurij73
    Tryed to add a new hard sdb (not formated) to my virtualbox Centos. Successfully extended an existing vg_localhost to /dev/sdb/ # lvdisplay --- Logical volume --- LV Path /dev/vg_localhost/lv_root LV Name lv_root VG Name vg_localhost LV UUID DkYX7D-DMud-vLaI-tfnz-xIJJ-VzHz-bRp3tO LV Write Access read/write LV Creation host, time localhost.centos, 2012-12-17 LV Status available # open 1 LV Size 18,03 GiB Current LE 4615 Segments 2 Allocation inherit Read ahead sectors auto - currently set to 256 Block device 253:0 lsblk NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT sdb 8:16 0 20G 0 disk +-vg_localhost-lv_root (dm-0) 253:0 0 18G 0 lvm / +-vg_localhost-lv_swap (dm-1) 253:1 0 2G 0 lvm [SWAP] sda 8:0 0 9G 0 disk +-sda1 8:1 0 500M 0 part /boot +-sda2 8:2 0 8,5G 0 part sr0 11:0 1 1024M 0 rom df -h /dev/mapper/vg_localhost-lv_root 6,5G 6,2G 256M 97% / tmpfs 499M 200K 499M 1% /dev/shm /dev/sda1 485M 78M 382M 17% /boot it still old sda in use, what i have to do further?

    Read the article

  • How to back up initial state of external backup drive?

    - by intuited
    I've picked up an HP Simplesave external drive. It comes with some fancy software that is of no use to me because I don't use Windows. Like many current consumer-targeted backup drives, the backup software is actually contained on the drive itself. I'd like to save the drive's initial state so that I can restore it if I decide to sell it. The backup box itself is somewhat customized: in addition to the hard drive device, it presents a CDROM-like device on /dev/sr0. I gather that the purpose of this cdrom device is to bootstrap via Windows autoplay the backup application which lives on the disk itself. I wouldn't suppose any guarantees about how it does this, so it seems important to preserve the exact state of the disk. The drive is formatted with a single 500GB NTFS partition. My initial thought was to use dd to dump the disk (/dev/sdb) itself, but this proved impractical, as the resulting file was not sparse. This seemed to be because the NTFS empty space is not filled with zeroes, but with a repeating series of 16 bytes. I tried gzipping the output of dd. This reduced to the file to a manageable size — the first 18GB was compressed to 81MB, versus 47MB to tarball the contents of the mounted filesystem — but it was very slow on my admittedly somewhat derelict Pentium M processor. The time to do that first 18GB was about 30 minutes. So I've resorted to dumping the disk state and partition data separately. I've dumped the partition state with sfdisk -d /dev/sdb > sfdisk.-d.out I've also created a compressed image of the NTFS partition (the only one on the disk) with ntfsclone --save-image --output - /dev/sdb1 | gzip -c > ntfsclone.img.gz Is there anything else I should do to ensure that I can restore the precise original state of the drive?

    Read the article

  • "Disk boot failure" error after installing Windows 7 on SSD

    - by Tony_Henrich
    I have a system with 3 SATA drives which runs fine. Got a new SSD drive and wanted to install a fresh Windows-7 on it. So I removed the boot drive and replaced it with the SSD drive. Installed Windows and when it was done, rebooted and now I get "Disk boot failure. Insert system disk and press enter" error message. I reinstall again and still same message. Removed the SSD and put back the original drive and I got the same message!! I checked the BIOS and things look good. Something is wrong. Two questions: 1- Why isn't the new Windows booting from the SSD? 2- Why isn't the machine booting using the previous working configuration anymore, after removing the SSD? I did connect it during the second Windows installation but it was the last drive in the SATA connector. Would Windows installer mess with its MBR sector?

    Read the article

  • Procedure for dual booting (2 copies of Win-7) off 2 partitions on same disk

    - by Sam Holder
    What procedure should I follow to set a dual boot (both Win-7 x64) on a machine where (ideally): Both operating systems will be installed on the same physical disk in different partitions When booting into either operating system the contents of the other OS partition disk will not be seen (this just seems safer) Other hard drives in the system will be visible by both OS's 1 copy of Win7 is already installed. Is it as simple as shrinking the existing volume and creating the partition, then sticking the CD in and booting off it and formatting the new partition and then installing another copy of windows onto the new partition? Or will that not work? Or are there gotchas?

    Read the article

  • Linux cannot alter partition table of main hard disk of my laptop

    - by djechelon
    I run openSUSE 12.2 on my ASUS N76VZ laptop. My problem is that I cannot alter the partition table of first hard disk /dev/sda1. YaST partitioner says it's unreadable, but actually it can read it but not alter it. It doesn't tell me anything else, except that I can wipe the partition table (having to reinstall Windows for the third time). Since I want to create new partitions on that disk, how do I fix the partition table layout? I could create new partition from Windows Computer Management and format them in Linux. I could do this, but it doesn't explain the problem

    Read the article

  • Can I recover files on a disk With 5% of start of disk completely wiped (overwritten with 1s)

    - by ARA
    Recently a virus attacked my pc and cleared 5% of my hard disk which has one partition I viewed the disk in a hex viewer program like active undelete ,cleared the virus data and overwrote it with 1s I want to recover a large file that is about 10gb, but no recovery tools seem to be able to recover any files. I want to know ,in theory, is this file recoverable ? I think that files are fragmented, researched about NTFS File System and i understand cluster information are just saved in MFT File ? Is there any way to recover file without a MFT structure ?

    Read the article

  • Detach Disk from deleted virtual machine

    - by user1628043
    I had an Virtual Machine running in Azure for a couple of weeks and suddenly it stopped responding. I shut it down and tried to restart it but that failed saying the VM faulted. I then deleted the VM which leaves the VHD file intact on my storage account. I was intending to try recreating a new VM using thie VHD from the first VM however, the OS disk and Data disk are both still marked as being attached to the original VM which no longer exists. Is there any way to detach these disks so I can use them to create a new VM?

    Read the article

  • scsi and ata entries for same hard drive under /dev/disk/by-id

    - by John Dibling
    I am trying to set up a ZFS pool using 4 bare drives which I have attached to my Ubuntu system via a SATA hot swap backplane. These are Hitachi SATA drives. When I list the contents of /dev/disk/by-id, I see two entries for each drive: root@scorpius:/dev/disk/by-id# ls | grep Hitachi ata-Hitachi_HDS5C3030ALA630_MJ1323YNG0ZJ7C ata-Hitachi_HDS5C3030ALA630_MJ1323YNG1064C ata-Hitachi_HDS5C3030ALA630_MJ1323YNG190AC ata-Hitachi_HDS5C3030ALA630_MJ1323YNG1DGPC scsi-SATA_Hitachi_HDS5C30_MJ1323YNG0ZJ7C scsi-SATA_Hitachi_HDS5C30_MJ1323YNG1064C scsi-SATA_Hitachi_HDS5C30_MJ1323YNG190AC scsi-SATA_Hitachi_HDS5C30_MJ1323YNG1DGPC I know these are the same drives because I wrote down the serial numbers, and all the other drives in this system are either Seagate or WD. The serial number for the first one, for example, is YNG0ZJ7C. Why are there two entries here for each drive? More to the point, when I create my ZFS pool which one should I use; the scsi- one or the ata- one?

    Read the article

  • df -h overreports disk space on VPS

    - by Rincewind42
    When I run the command df -h on my new Ubuntu linux vServer I get the following: # df -h Filesystem Size Used Avail Use% Mounted on /dev/hdv1 466G 33G 434G 7% / none 16M 0 16M 0% /tmp Running du -sh gives # du -sh du: cannot access `./proc/13624/task/13624/fd/4': No such file or directory du: cannot access `./proc/13624/task/13624/fdinfo/4': No such file or directory du: cannot access `./proc/13624/fd/4': No such file or directory du: cannot access `./proc/13624/fdinfo/4': No such file or directory 952M . The VPS should only have 5Gb of disk space but df reports 466Gb. How can I view the correct amount of disk space?

    Read the article

  • External disk not working with Mac OS X 10.5

    - by ctx2002
    Hi: My OS is 10.5.7. I have an external hard disk, formatted as Mac OS Extended (Journaled), connected to my Mac machine through USB cable. I have used it for a while, but now it is not working. Error showed in /var/log/system.log. USBF: 2521.384 AppleUSBEHCI[0xa515800]::Found a transaction which hasn't moved in 5 seconds on bus 0xfd, timing out! (Addr: 0, EP: 0) ..... ...... kernel[0]: USBF: 2588.616 [0xa6baa00] The IOUSBFamily was not able to enumerate a device. Luckily, in my work place there is a Mac with OS 10.4, so I had plugged the disk into the 10.4 machine and it worked!!! I did checked "System Profiler" on both machines (10.5, 10.4). Under usb section, for 10.5 it shows USBEHCI, under 10.4, it shows USBOHCI. I am not a expert on USB Device , can any one tell me why 10.5 cause the problem. it was worked under 10.5

    Read the article

  • Recovering data from a corrupted disk

    - by r_honey
    I use an external harddisk to backup my data (it had 3 partitions). Last week when I plugged it in, the OS (Win 7) hung up and I had to force re-boot the machine. When I turned it back on, the system just did not detect the hard-disk. It was last Sunday and I had to give up after sometime. Now I return back next Sunday (today) and when I plug it back-in to the machine, the OS detects the disk as well as all the 3 partitions on it. But it says all 3 are unformatted and I cant access any of them. Is there any way to recover data from the 3 partitions (I tried PC File Recovery and Recuva from PiriForm but neither detected these partitions).

    Read the article

  • Use `dd` linux program to save / recover a disk's MBR

    - by Graduate
    I have an Ubuntu OS installed on my laptop. I want to install Windows 7 as well to another disk partition (I will do it by recovering it from a special partition on my laptop). After installing Windows, I want to recover my hard drive MBR to be able to load Ubuntu. I have a plan to use linux dd program: 1) (Before installing, perform this command in Linux) dd if=/dev/sda of=/home/user/mbr_backup bs=512 count=1 2) (after installing, load Ubuntu Live CD and launch this) dd if=/home/user/mbr_backup of=/dev/sda bs=512 count=1 3) Load Ubuntu on PC and re-configure the GRUB2 to be able start Windows I need your advice, I want to be sure I won't damage the disk (it's partition table).

    Read the article

  • how to recover data from my disk - I accidentally copied with dd an iso on it

    - by sijoune
    I wanted to create a bootable usb from an iso image and i accidentally put as the output of the dd, instead of my usb drive, one of my hard disks. The iso was 3,3 GB and my disk is 1TB! And it was almost full. Can i at least restore the data that has not been overwritten? Right now i can't even mount it. I get this error: Error mounting /dev/sdd1 at /media/main/UDF Volume: Command-line `mount -t "udf" -o "uhelper=udisks2,nodev,nosuid,uid=1000,gid=1000,iocharset=utf8,umask=0077" "/dev/sdd1" "/media/main/UDF Volume"' exited with non-zero exit status 32: mount: wrong fs type, bad option, bad superblock on /dev/sdd1, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so Also since i know which filesystem my disk used if i reformat it to this filesystem is there any chance i can mount it and retrieve the rest of the files?

    Read the article

  • repairing or retrieving video off a cracked disk

    - by Tori Hisey
    My disk has a thin cracked right through the one side. right around the crack it looks like it has water damage but im pretty sure it was caused from the crack. will tape work for this? its a dvd of us in jamaica swimming with dolphins and i havent even watched it yet, it got ruined in my suitcase. If there is no way to repair it, is there somewhere that i can take it so they might be able to somehow get the video off of it and onto another disk? any suggestions would be helpful. Thanks

    Read the article

  • why my test performance class gives me inconsistent results even after proper warm-up?

    - by colinfang
    i made a class which helps me measure time for any methods in Ticks. Basically, it runs testing method 100x, and force GC, then it records time taken for another 100x method runs. x64 release ctrl+f5 VS2012/VS2010 the results are following: 2,914 2,909 2,913 2,909 2,908 2,907 2,909 2,998 2,976 2,855 2,446 2,415 2,435 2,401 2,402 2,402 2,399 2,401 2,401 2,400 2,399 2,400 2,404 2,402 2,401 2,399 2,400 2,402 2,404 2,403 2,401 2,403 2,401 2,400 2,399 2,414 2,405 2,401 2,407 2,399 2,401 2,402 2,401 2,404 2,401 2,404 2,405 2,368 1,577 1,579 1,626 1,578 1,576 1,578 1,577 1,577 1,576 1,578 1,576 1,578 1,577 1,578 1,576 1,578 1,577 1,579 1,585 1,576 1,579 1,577 1,579 1,578 1,579 1,577 1,578 1,577 1,578 1,576 1,578 1,577 1,578 1,599 1,579 1,578 1,582 1,576 1,578 1,576 1,579 1,577 1,578 1,577 1,591 1,577 1,578 1,578 1,576 1,578 1,576 1,578 As you can see there are 3 phases, first is ~2,900, second is ~2,400, then ~1,550 What might be the reason to cause it? the test performance class code follows: public static void RunTests(Func<long> myTest) { const int numTrials = 100; Stopwatch sw = new Stopwatch(); double[] sample = new double[numTrials]; Console.WriteLine("Checksum is {0:N0}", myTest()); sw.Start(); myTest(); sw.Stop(); Console.WriteLine("Estimated time per test is {0:N0} ticks\n", sw.ElapsedTicks); for (int i = 0; i < numTrials; i++) { myTest(); } GC.Collect(); string testName = myTest.Method.Name; Console.WriteLine("----> Starting benchmark {0}\n", myTest.Method.Name); for (int i = 0; i < numTrials; i++) { sw.Restart(); myTest(); sw.Stop(); sample[i] = sw.ElapsedTicks; } double testResult = DataSetAnalysis.Report(sample); for (int j = 0; j < numTrials; j = j + 5) Console.WriteLine("{0,8:N0} {1,8:N0} {2,8:N0} {3,8:N0} {4,8:N0}", sample[j], sample[j + 1], sample[j + 2], sample[j + 3], sample[j + 4]); Console.WriteLine("\n----> End of benchmark"); }

    Read the article

  • Web Site Performance and Assembly Versioning – Part 2 Versioning Combined Files Using Subversion

    - by capgpilk
    Ok so it took a while to post this second part. Many apologies, we had a big roll out of a new platform at work and many things had to get sidelined. So this is the second part in a short series of website performance and using versioning to help improve it. Minification and Concatination of JavaScript and CSS Files Versioning Combined Files Using Subversion – this post Versioning Combined Files Using Mercurial – published shortly In the previous post we used AjaxMin to shrink js and css files then concatenated them into one file each which had the file name of site-script.combined.min.js and site-style.combined.min.css. These file names are fine, but you can configure IIS 7 to cache these static files and so lower the amount of data transferred between server and client. This is done by editing the response headers in IIS. 1. In IIS7 Manager, choose the directory where these files are located and select HTTP Response Headers. 2. Check the Expire Web Content and set a time period well into the future. 3. When refreshing the web page, the server will respond with HTTP 304 forcing the browser to retrieve the file from its cache. 4. As can be seen in FireBug, the Cache-Control header has a max age of 31536000 seconds which equates to 365 days.   The server will always send this HTTP 304 message unless the file changes forcing it to send new content. To help force this we can change the file name based on the latest build using the SVN revision number in the filename. So we have lowered data transfer on content that hasn’t changed, but forced it to be sent when you have made a change to the css or js files. Now to get the SVN revision number in to the file name. 1. Import the MSBuildCommunityTasks targets which can be dowloaded from here. 1: <Import Project="$(MSBuildExtensionsPath) 2: \MSBuildCommunityTasks 3: \MSBuild.Community.Tasks.Targets" /> 2. Edit the BeforeBuild target to call out to svn and get the latest revision 1: <SvnVersion LocalPath="$(MSBuildProjectDirectory)" 2: ToolPath="$(ProgramFiles)\VisualSVN Server\bin"> 3: <Output TaskParameter="Revision" PropertyName="Revision" /> 4: </SvnVersion> 3. Set it to update the project AssemblyInfo.cs file for the svn revision. 1: <FileUpdate Files="Properties\AssemblyInfo.cs" 2: Regex="(\d+)\.(\d+)\.(\d+)\.(\d+)" 3: ReplacementText="$1.$2.$3.$(Revision)" /> 4. Now edit the AfterBuild target to get the full dll version. You could combine these two steps and just get the version from svn, I am working on one project that updates the AssemblyInfo file and another project that allows manual editing of the file, but needs that version within the file name; so I just combined the two for this post. 1: <MSBuild.ExtensionPack.Framework.Assembly 2: TaskAction="GetInfo" 3: NetAssembly="$(OutputPath)\mydll.dll"> 4: <Output TaskParameter="OutputItems" ItemName="Info" /> 5: </MSBuild.ExtensionPack.Framework.Assembly> 6: <Message Text="Version: %(Info.AssemblyVersion)" 7: Importance="High" /> 5. Use this Info.AssemblyVersion to write out the combined css and js files as described in the last post. 1: <WriteLinestoFile File="Scripts\site-%(Info.AssemblyVersion).combined.min.js" 2: Lines="@(JSLinesSite)" Overwrite="true" />   In the next post I will cover doing the same, but for a Mercurial repository.

    Read the article

  • quick look at: dm_db_index_physical_stats

    - by fatherjack
    A quick look at the key data from this dmv that can help a DBA keep databases performing well and systems online as the users need them. When the dynamic management views relating to index statistics became available in SQL Server 2005 there was much hype about how they can help a DBA keep their servers running in better health than ever before. This particular view gives an insight into the physical health of the indexes present in a database. Whether they are use or unused, complete or missing some columns is irrelevant, this is simply the physical stats of all indexes; disabled indexes are ignored however. In it’s simplest form this dmv can be executed as:   The results from executing this contain a record for every index in every database but some of the columns will be NULL. The first parameter is there so that you can specify which database you want to gather index details on, rather than scan every database. Simply specifying DB_ID() in place of the first NULL achieves this. In order to avoid the NULLS, or more accurately, in order to choose when to have the NULLS you need to specify a value for the last parameter. It takes one of 4 values – DEFAULT, ‘SAMPLED’, ‘LIMITED’ or ‘DETAILED’. If you execute the dmv with each of these values you can see some interesting details in the times taken to complete each step. DECLARE @Start DATETIME DECLARE @First DATETIME DECLARE @Second DATETIME DECLARE @Third DATETIME DECLARE @Finish DATETIME SET @Start = GETDATE() SELECT * FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, DEFAULT) AS ddips SET @First = GETDATE() SELECT * FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, 'SAMPLED') AS ddips SET @Second = GETDATE() SELECT * FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, 'LIMITED') AS ddips SET @Third = GETDATE() SELECT * FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, 'DETAILED') AS ddips SET @Finish = GETDATE() SELECT DATEDIFF(ms, @Start, @First) AS [DEFAULT] , DATEDIFF(ms, @First, @Second) AS [SAMPLED] , DATEDIFF(ms, @Second, @Third) AS [LIMITED] , DATEDIFF(ms, @Third, @Finish) AS [DETAILED] Running this code will give you 4 result sets; DEFAULT will have 12 columns full of data and then NULLS in the remainder. SAMPLED will have 21 columns full of data. LIMITED will have 12 columns of data and the NULLS in the remainder. DETAILED will have 21 columns full of data. So, from this we can deduce that the DEFAULT value (the same one that is also applied when you query the view using a NULL parameter) is the same as using LIMITED. Viewing the final result set has some details that are worth noting: Running queries against this view takes significantly longer when using the SAMPLED and DETAILED values in the last parameter. The duration of the query is directly related to the size of the database you are working in so be careful running this on big databases unless you have tried it on a test server first. Let’s look at the data we get back with the DEFAULT value first of all and then progress to the extra information later. We know that the first parameter that we supply has to be a database id and for the purposes of this blog we will be providing that value with the DB_ID function. We could just as easily put a fixed value in there or a function such as DB_ID (‘AnyDatabaseName’). The first columns we get back are database_id and object_id. These are pretty explanatory and we can wrap those in some code to make things a little easier to read: SELECT DB_NAME([ddips].[database_id]) AS [DatabaseName] , OBJECT_NAME([ddips].[object_id]) AS [TableName] … FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, NULL) AS ddips  gives us   SELECT DB_NAME([ddips].[database_id]) AS [DatabaseName] , OBJECT_NAME([ddips].[object_id]) AS [TableName], [i].[name] AS [IndexName] , ….. FROM [sys].[dm_db_index_physical_stats](DB_ID(), NULL, NULL, NULL, NULL) AS ddips INNER JOIN [sys].[indexes] AS i ON [ddips].[index_id] = [i].[index_id] AND [ddips].[object_id] = [i].[object_id]     These handily tie in with the next parameters in the query on the dmv. If you specify an object_id and an index_id in these then you get results limited to either the table or the specific index. Once again we can place a  function in here to make it easier to work with a specific table. eg. SELECT * FROM [sys].[dm_db_index_physical_stats] (DB_ID(), OBJECT_ID(‘AdventureWorks2008.Person.Address’) , 1, NULL, NULL) AS ddips   Note: Despite me showing that functions can be placed directly in the parameters for this dmv, best practice recommends that functions are not used directly in the function as it is possible that they will fail to return a valid object ID. To be certain of not passing invalid values to this function, and therefore setting an automated process off on the wrong path, declare variables for the OBJECT_IDs and once they have been validated, use them in the function: DECLARE @db_id SMALLINT; DECLARE @object_id INT; SET @db_id = DB_ID(N’AdventureWorks_2008′); SET @object_id = OBJECT_ID(N’AdventureWorks_2008.Person.Address’); IF @db_id IS NULL BEGINPRINT N’Invalid database’; ENDELSE IF @object_id IS NULL BEGINPRINT N’Invalid object’; ENDELSE BEGINSELECT * FROM sys.dm_db_index_physical_stats (@db_id, @object_id, NULL, NULL , ‘LIMITED’); END; GO In cases where the results of querying this dmv don’t have any effect on other processes (i.e. simply viewing the results in the SSMS results area)  then it will be noticed when the results are not consistent with the expected results and in the case of this blog this is the method I have used. So, now we can relate the values in these columns to something that we recognise in the database lets see what those other values in the dmv are all about. The next columns are: We’ll skip partition_number, index_type_desc, alloc_unit_type_desc, index_depth and index_level  as this is a quick look at the dmv and they are pretty self explanatory. The final columns revealed by querying this view in the DEFAULT mode are avg_fragmentation_in_percent. This is the amount that the index is logically fragmented. It will show NULL when the dmv is queried in SAMPLED mode. fragment_count. The number of pieces that the index is broken into. It will show NULL when the dmv is queried in SAMPLED mode. avg_fragment_size_in_pages. The average size, in pages, of a single fragment in the leaf level of the IN_ROW_DATA allocation unit. It will show NULL when the dmv is queried in SAMPLED mode. page_count. Total number of index or data pages in use. OK, so what does this give us? Well, there is an obvious correlation between fragment_count, page_count and avg_fragment_size-in_pages. We see that an index that takes up 27 pages and is in 3 fragments has an average fragment size of 9 pages (27/3=9). This means that for this index there are 3 separate places on the hard disk that SQL Server needs to locate and access to gather the data when it is requested by a DML query. If this index was bigger than 72KB then having it’s data in 3 pieces might not be too big an issue as each piece would have a significant piece of data to read and the speed of access would not be too poor. If the number of fragments increases then obviously the amount of data in each piece decreases and that means the amount of work for the disks to do in order to retrieve the data to satisfy the query increases and this would start to decrease performance. This information can be useful to keep in mind when considering the value in the avg_fragmentation_in_percent column. This is arrived at by an internal algorithm that gives a value to the logical fragmentation of the index taking into account the multiple files, type of allocation unit and the previously mentioned characteristics if index size (page_count) and fragment_count. Seeing an index with a high avg_fragmentation_in_percent value will be a call to action for a DBA that is investigating performance issues. It is possible that tables will have indexes that suffer from rapid increases in fragmentation as part of normal daily business and that regular defragmentation work will be needed to keep it in good order. In other cases indexes will rarely become fragmented and therefore not need rebuilding from one end of the year to another. Keeping this in mind DBAs need to use an ‘intelligent’ process that assesses key characteristics of an index and decides on the best, if any, defragmentation method to apply should be used. There is a simple example of this in the sample code found in the Books OnLine content for this dmv, in example D. There are also a couple of very popular solutions created by SQL Server MVPs Michelle Ufford and Ola Hallengren which I would wholly recommend that you review for much further detail on how to care for your SQL Server indexes. Right, let’s get back on track then. Querying the dmv with the fifth parameter value as ‘DETAILED’ takes longer because it goes through the index and refreshes all data from every level of the index. As this blog is only a quick look a we are going to skate right past ghost_record_count and version_ghost_record_count and discuss avg_page_space_used_in_percent, record_count, min_record_size_in_bytes, max_record_size_in_bytes and avg_record_size_in_bytes. We can see from the details below that there is a correlation between the columns marked. Column 1 (Page_Count) is the number of 8KB pages used by the index, column 2 is how full each page is (how much of the 8KB has actual data written on it), column 3 is how many records are recorded in the index and column 4 is the average size of each record. This approximates to: ((Col1*8) * 1024*(Col2/100))/Col3 = Col4*. avg_page_space_used_in_percent is an important column to review as this indicates how much of the disk that has been given over to the storage of the index actually has data on it. This value is affected by the value given for the FILL_FACTOR parameter when creating an index. avg_record_size_in_bytes is important as you can use it to get an idea of how many records are in each page and therefore in each fragment, thus reinforcing how important it is to keep fragmentation under control. min_record_size_in_bytes and max_record_size_in_bytes are exactly as their names set them out to be. A detail of the smallest and largest records in the index. Purely offered as a guide to the DBA to better understand the storage practices taking place. So, keeping an eye on avg_fragmentation_in_percent will ensure that your indexes are helping data access processes take place as efficiently as possible. Where fragmentation recurs frequently then potentially the DBA should consider; the fill_factor of the index in order to leave space at the leaf level so that new records can be inserted without causing fragmentation so rapidly. the columns used in the index should be analysed to avoid new records needing to be inserted in the middle of the index but rather always be added to the end. * – it’s approximate as there are many factors associated with things like the type of data and other database settings that affect this slightly.  Another great resource for working with SQL Server DMVs is Performance Tuning with SQL Server Dynamic Management Views by Louis Davidson and Tim Ford – a free ebook or paperback from Simple Talk. Disclaimer – Jonathan is a Friend of Red Gate and as such, whenever they are discussed, will have a generally positive disposition towards Red Gate tools. Other tools are often available and you should always try others before you come back and buy the Red Gate ones. All code in this blog is provided “as is” and no guarantee, warranty or accuracy is applicable or inferred, run the code on a test server and be sure to understand it before you run it on a server that means a lot to you or your manager.

    Read the article

  • Why is LSHW Only listing one of my two HDDs?

    - by Mark
    I have a 120GB HDD and a 1TB HDD in the system. I installed Ubuntu Server using LVM on the 120GB. After installation I added the 1TB to the existing volume group and added 10GB to /home as a test. My understanding is that lshw is supposed to list hardware. What's the difference here? mark@server:~$ sudo lshw -short -c disk H/W path Device Class Description ========================================================= /0/100/1f.2/0 /dev/sda disk 120GB ST3120026AS /0/100/1f.2/1 /dev/cdrom disk DVD+-RW GH50N /0/1/0.0.0 /dev/sdc disk SCSI Disk /0/1/0.0.1 /dev/sdd disk SCSI Disk /0/1/0.0.2 /dev/sde disk SCSI Disk /0/1/0.0.3 /dev/sdf disk SCSI Disk The 1TB only shows up as a volume, not as a disk. mark@server:~$ sudo lshw -short .... /0/100/1f.2/0 /dev/sda disk 120GB ST3120026AS /0/100/1f.2/0/1 /dev/sda1 volume 476MiB Linux filesystem partition /0/100/1f.2/0/2 /dev/sda2 volume 111GiB Linux LVM Physical Volume partition /0/100/1f.2/1 /dev/cdrom disk DVD+-RW GH50N /0/100/1f.2/0.0.0 /dev/sdb volume 931GiB WDC WD1001FALS-0 Thanks, Mark

    Read the article

  • SQL SERVER – SQL Server Misconceptions and Resolution – A Practical Perspective – TechEd 2012 India

    - by pinaldave
    TechEd India 2012 is just around the corner and I will be presenting there in two different sessions. On the very first day of this event, my presentation will be all about SQL Server Misconceptions and Resolution – A Practical Perspective. The dictionary tells us that a “misconception” means a view or opinion that is incorrect and is based on faulty thinking or understanding. In SQL Server, there are so many misconceptions. In fact, when I hear some of these misconceptions, I feel like fainting at that very moment! Seriously, at one time, I came across the scenario where instead of using INSERT INTO…SELECT, the developer used CURSOR believing that cursor is faster (duh!). Here is the link the blog post related to this. Pinal and Vinod in 2009 I have been presenting in TechEd India for last three years. This is my fourth opportunity to present a technical session on SQL Server. Just like the previous years, I decided to present something different. Here is a novelty of this year: I will be presenting this session with Vinod Kumar. Vinod Kumar and I have a great synergy when we work together. So far, we have written one SQL Server Interview Questions and Answers book and 2 video courses: (1) SQL Server Questions and Answers (2) SQL Server Performance: Indexing Basics. Pinal and Vinod in 2011 When we sat together and started building an outline for this course, we had many options in mind for this tango session. However, we have decided that we will make this session as lively as possible while keeping it natural at the same time. We know our flow and we know our conversation highlight, but we do not know what exactly each of us is going to present. We have decided to challenge each other on stage and push each other’s knowledge to the verge. We promise that the session will be entertaining with lots of SQL Server trivia, tips and tricks. Here are the challenges that I’ll take on: I will puzzle Vinod with my difficult questions I will present such misconception that Vinod will have no resolution for it. I need your help.  Will you help me stump Vinod? If yes, come and attend our session and join me to prove that together we are superior (a friendly brain clash, but we must win!). SQL Server enthusiasts and SQL Server fans are going to have gala time at #TechEdIn as we have a very solid lineup of the speaker and extremely interesting sessions at TechEdIn. Read the complete blog post of Vinod. Session Details Title: SQL Server Misconceptions and Resolution – A Practical Perspective (Add to Calendar) Abstract: “Earth is flat”! – An ancient common misconception, which has been proven incorrect as we progressed in modern times. In this session we will see various database misconceptions prevailing and their resolution with the aid of the demos. In this unique session audience will be part of the conversation and resolution. Date and Time: March 21, 2012, 15:15 to 16:15 Location: Hotel Lalit Ashok - Kumara Krupa High Grounds, Bengaluru – 560001, Karnataka, India. Add to Calendar Please submit your questions in the comments area and I will be for sure discussing them during my session. If I pick your question to discuss during my session, here is your gift I commit right now – SQL Server Interview Questions and Answers Book. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Interview Questions and Answers, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology Tagged: TechEd, TechEdIn

    Read the article

  • SQL SERVER – Partition Parallelism Support in expressor 3.6

    - by pinaldave
    I am very excited to learn that there is a new version of expressor’s data integration platform coming out in March of this year.  It will be version 3.6, and I look forward to using it and telling everyone about it.  Let me describe a little bit more about what will be so great in expressor 3.6: Greatly enhanced user interface Parallel Processing Bulk Artifact Upgrading The User Interface First let me cover the most obvious enhancements. The expressor Studio user interface (UI) has had some significant work done. Kudos to the expressor Engineering team; the entire UI is a visual masterpiece that is very responsive and intuitive. The improvements are more than just eye candy; they provide significant productivity gains when developing expressor Dataflows. Operator shape icons now include a description that identifies the function of each operator, instead of having to guess at the function by the icon. Operator shapes and highlighting depict the current function and status: Disabled, enabled, complete, incomplete, and error. Each status displays an appropriate message in the message panel with correction suggestions. Floating or docking property panels provide descriptive tool tips for each property as well as auto resize when adjusting the canvas, without having to search Help or the need to scroll around to get access to the property. Progress and status indicators let you know when an operation is working. “No limit” canvas with snap-to-grid allows automatic sizing and accurate positioning when you have numerous operators in the Dataflow. The inline tool bar offers quick access to pan, zoom, fit and overview functions. Selecting multiple artifacts with a right click context allows you to easily manage your workspace more efficiently. Partitioning and Parallel Processing Partitioning allows each operator to process multiple subsets of records in parallel as opposed to processing all records that flow through that operator in a single sequential set. This capability allows the user to configure the expressor Dataflow to run in a way that most efficiently utilizes the resources of the hardware where the Dataflow is running. Partitions can exist in most individual operators. Using partitions increases the speed of an expressor data integration application, therefore improving performance and load times. With the expressor 3.6 Enterprise Edition, expressor simplifies enabling parallel processing by adding intuitive partition settings that are easy to configure. Bulk Artifact Upgrading Bulk Artifact Upgrading sounds a bit intimidating, but it actually is not and it is a welcome addition to expressor Studio. In past releases, users were prompted to confirm that they wanted to upgrade their individual artifacts only when opened. This was a cumbersome and repetitive process. Now with bulk artifact upgrading, a user can easily select what artifact or group of artifacts to upgrade all at once. As you can see, there are many new features and upgrade options that will prove to make expressor Studio quicker and more efficient.  I hope I’m not the only one who is excited about all these new upgrades, and that I you try expressor and share your experience with me. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

    Read the article

< Previous Page | 85 86 87 88 89 90 91 92 93 94 95 96  | Next Page >